AudioControl is probably best known for their great equalizers and crossovers, and the EQL is one of the reasons why. AudioControl pretty much wrote the book on "EQ-ing" your sound system, and the EQL works wonders with any 2-channel audio system – even factory headunits! The EQL is a 2-channel, 13-band, dual-bandwidth equalizer with level matching circuitry to allow for either speaker-level or line-level inputs. The EQL also features a high voltage PWM power supply for increased headroom and noise rejection, and a built-in Programmable Frequency Match (PFM) subsonic filter to protect your speakers and avoid wasted amplifier power. Made in the USA; White in color.